1. Field of the Invention
The present invention relates to acoustic transducers, and more particularly to a single element cantilever mounted transducer for measuring shear wave attenuation in sediments.
2. Description of the Prior Art
In oceanographic investigations it is desired to know as much as possible about the ocean environment including the characteristics of saturated sediments. Some of the sediment characteristics desired are shear wave attenuation and speed. Old measurement methods include resonant column torsion methods which have a limited frequency range. Wave propagation methods using unmounted bimorph elements encased in epoxy resin also have been used with some success, but suffer from a lack of repeatability due to transducer-to-sediment coupling sensitivity, insufficient path length due to low output of the transducers, and electrical interference which leads to an inability to determine the starting time of the arrival. Multiple element transducers have been used with some success but their sensitivity is insufficient and they are difficult to manufacture since element poling and response must be considered. Therefore, it is desired to have a shear wave transducer which provides repeatable shear wave attenuation and speed measurements in saturated sediments over appreciable transmission paths over a relatively wide frequency range such as 1 KHz to 20 KHz.